Watch: Serena Williams into semis against Barty in Aussie tuneup

Barty and Williams both said they're looking forward to the match, despite the close proximity to a major.

Melbourne: Most things about this week leading into a major are different for Serena Williams.

The 23-time Grand Slam champion got to try something new Friday, too, needing a match tiebreaker to beat fellow American Danielle Collins 6-2, 4-6, 10-6 and set up a semifinal against top-ranked Ash Barty in the Yarra River Classic.

"I felt good to get through that in a tiebreaker," said Williams, who usually doesn't play in the week before a Grand Slam tournament. "Definitely different."

That's been the theme for this Australian Open, which was delayed three weeks so that all players and their entourages could spend 14 days in hotel quarantine under the strict regulations in place for the COVID-19 pandemic.

A day after all matches in six tournaments were postponed so that 160 players and 507 people overall could isolate and undergo testing because a worker at a quarantine hotel returned a positive test, there were 70 matches on the order of play as organizers tried to cram all scheduled lead-in matches into three days. Tennis Australia said all tests were negative. The Australian Open starts Monday.

To speed things up a little, 17 courts were being used and women's matches were reduced to two regular sets with a 10-point match tiebreaker if required.

Barty also got her first taste of the modified scoring system introduced to shorten matches in a disrupted schedule, dominating a match tiebreaker to beat Shelby Rogers 7-5, 2-6, 10-4.

Barty and Williams both said they're looking forward to the match, despite the close proximity to a major.

"It's definitely a good opportunity to see where I'm going against the current No. 1, that's really important for me," Williams said.

"Obviously I think for her, as well, to see where she's going against my game.

"It's been a long 12 months. Tennis has been played but not really, so ... hopefully this is like a new year where things will be different."

Garbine Muguruza beat defending Australian Open champion Sofia Kenin 6-2, 6-2 to advance to the semifinals, reversing their result of their 2020 final at Melbourne Park. She will next play No. 8 Marketa Vondrousova.

AZARENKA ADVANCES

Two-time Australian Open champion Victoria Azarenka beat Yulia Putintseva 6-4, 1-6, 11-9 to advance at the Grampians Trophy, an event staged for the players forced into hard lockdown during quarantine.

Sorana Cirstea upset Belinda Bencic, the highest-ranked player in the tournament, 7-5, 6-2 before a clap of thunder and a rain shower suspended play on outside courts.

GERMANY UPSETS DEFENDING CHAMPS SERBIA

Alexander Zverev rebounded from a narrow singles loss to Novak Djokovic to help Germany win the deciding doubles match that earned the team a spot in the ATP Cup semifinals at the expense of defending champion Serbia.

Jan-Lennard Struff beat Dusan Lajovic 3-6, 6-3, 6-4 to give Germany a 1-0 lead in Group A, but top-ranked Djokovic leveled it up with a 6-7 (3), 6-2, 7-5 win over Zverev.

Struff and Zverev combined for a 7-6 (4), 5-7, 10-7 win over Nikola Cacic and Djokovic in the doubles, advancing to a semifinal against Russia on Saturday.

Pablo Carreno Busta clinched Spain a semifinal spot with a 6-3, 6-4 win over Michail Pervolarakis in the opening singles match against Greece. The win ensured Spain had enough points to top Group B, which also includes Australia.

No. 2-ranked Rafael Nadal skipped the encounter against Greece to give his sore back more time to rest, leaving No. 16-ranked Carreno Busta and No. 13-ranked Roberto Bautista Agut again to fill the singles spots.

"I knew we needed this point," Carreno Busta said in his on-court interview. "With this victory, we are into the semifinals, so it was very important to us."

Greece rallied for a 2-1 win over Spain, with Stefanos Tsitsipas beating Roberto Bautista 7-5, 7-5 and then combining with Pervolarakis in the deciding doubles match which lasted only one game before the Spanish pair retired.

WAWRINKA WINS, KYRGIOS "LOSES" RACKET

Top-ranked Stan Wawrinka beat Alex Bolt 6-4, 4-6, 7-6 (5) to move into the quarterfinals of the Murray River Open along with No. 3 Felix Auger-Aliassime and No. 4 Borna Coric, who beat local favorite Nick Kyrgios 6-3, 6-4. A frustrated Kyrgios smashed his racket and threw it out of the 1573 Arena.